lwn.git/kernel/trace, branch docs-5.0-fix

Remove 'type' argument from access_ok() function

2019-01-04T02:57:57+00:00

Nobody has actually used the type (VERIFY_READ vs VERIFY_WRITE) argument of the user address range verification function since we got rid of the old racy i386-only code to walk page tables by hand. It existed because the original 80386 would not honor the write protect bit when in kernel mode, so you had to do COW by hand before doing any user access. But we haven't supported that in a long time, and these days the 'type' argument is a purely historical artifact. A discussion about extending 'user_access_begin()' to do the range checking resulted this patch, because there is no way we're going to move the old VERIFY_xyz interface to that model. And it's best done at the end of the merge window when I've done most of my merges, so let's just get this done once and for all. This patch was mostly done with a sed-script, with manual fix-ups for the cases that weren't of the trivial 'access_ok(VERIFY_xyz' form. There were a couple of notable cases: - csky still had the old "verify_area()" name as an alias. - the iter_iov code had magical hardcoded knowledge of the actual values of VERIFY_{READ,WRITE} (not that they mattered, since nothing really used it) - microblaze used the type argument for a debug printout but other than those oddities this should be a total no-op patch. I tried to fix up all architectures, did fairly extensive grepping for access_ok() uses, and the changes are trivial, but I may have missed something. Any missed conversion should be trivially fixable, though. Signed-off-by: Linus Torvalds

Merge tag 'trace-v4.21' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

2018-12-31T19:46:59+00:00

Pull tracing updates from Steven Rostedt: - Rework of the kprobe/uprobe and synthetic events to consolidate all the dynamic event code. This will make changes in the future easier. - Partial rewrite of the function graph tracing infrastructure. This will allow for multiple users of hooking onto functions to get the callback (return) of the function. This is the ground work for having kprobes and function graph tracer using one code base. - Clean up of the histogram code that will facilitate adding more features to the histograms in the future. - Addition of str_has_prefix() and a few use cases. There currently is a similar function strstart() that is used in a few places, but only returns a bool and not a length. These instances will be removed in the future to use str_has_prefix() instead. - A few other various clean ups as well. * tag 'trace-v4.21' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (57 commits) tracing: Use the return of str_has_prefix() to remove open coded numbers tracing: Have the historgram use the result of str_has_prefix() for len of prefix tracing: Use str_has_prefix() instead of using fixed sizes tracing: Use str_has_prefix() helper for histogram code string.h: Add str_has_prefix() helper function tracing: Make function ‘ftrace_exports’ static tracing: Simplify printf'ing in seq_print_sym tracing: Avoid -Wformat-nonliteral warning tracing: Merge seq_print_sym_short() and seq_print_sym_offset() tracing: Add hist trigger comments for variable-related fields tracing: Remove hist trigger synth_var_refs tracing: Use hist trigger's var_ref array to destroy var_refs tracing: Remove open-coding of hist trigger var_ref management tracing: Use var_refs[] for hist trigger reference checking tracing: Change strlen to sizeof for hist trigger static strings tracing: Remove unnecessary hist trigger struct field tracing: Fix ftrace_graph_get_ret_stack() to use task and not current seq_buf: Use size_t for len in seq_buf_puts() seq_buf: Make seq_buf_puts() null-terminate the buffer arm64: Use ftrace_graph_get_ret_stack() instead of curr_ret_stack ...

Merge tag 'for-4.21/block-20181221' of git://git.kernel.dk/linux-block

2018-12-28T21:19:59+00:00

Pull block updates from Jens Axboe: "This is the main pull request for block/storage for 4.21. Larger than usual, it was a busy round with lots of goodies queued up. Most notable is the removal of the old IO stack, which has been a long time coming. No new features for a while, everything coming in this week has all been fixes for things that were previously merged. This contains: - Use atomic counters instead of semaphores for mtip32xx (Arnd) - Cleanup of the mtip32xx request setup (Christoph) - Fix for circular locking dependency in loop (Jan, Tetsuo) - bcache (Coly, Guoju, Shenghui) * Optimizations for writeback caching * Various fixes and improvements - nvme (Chaitanya, Christoph, Sagi, Jay, me, Keith) * host and target support for NVMe over TCP * Error log page support * Support for separate read/write/poll queues * Much improved polling * discard OOM fallback * Tracepoint improvements - lightnvm (Hans, Hua, Igor, Matias, Javier) * Igor added packed metadata to pblk. Now drives without metadata per LBA can be used as well. * Fix from Geert on uninitialized value on chunk metadata reads. * Fixes from Hans and Javier to pblk recovery and write path. * Fix from Hua Su to fix a race condition in the pblk recovery code. * Scan optimization added to pblk recovery from Zhoujie. * Small geometry cleanup from me. - Conversion of the last few drivers that used the legacy path to blk-mq (me) - Removal of legacy IO path in SCSI (me, Christoph) - Removal of legacy IO stack and schedulers (me) - Support for much better polling, now without interrupts at all. blk-mq adds support for multiple queue maps, which enables us to have a map per type. This in turn enables nvme to have separate completion queues for polling, which can then be interrupt-less. Also means we're ready for async polled IO, which is hopefully coming in the next release. - Killing of (now) unused block exports (Christoph) - Unification of the blk-rq-qos and blk-wbt wait handling (Josef) - Support for zoned testing with null_blk (Masato) - sx8 conversion to per-host tag sets (Christoph) - IO priority improvements (Damien) - mq-deadline zoned fix (Damien) - Ref count blkcg series (Dennis) - Lots of blk-mq improvements and speedups (me) - sbitmap scalability improvements (me) - Make core inflight IO accounting per-cpu (Mikulas) - Export timeout setting in sysfs (Weiping) - Cleanup the direct issue path (Jianchao) - Export blk-wbt internals in block debugfs for easier debugging (Ming) - Lots of other fixes and improvements" * tag 'for-4.21/block-20181221' of git://git.kernel.dk/linux-block: (364 commits) kyber: use sbitmap add_wait_queue/list_del wait helpers sbitmap: add helpers for add/del wait queue handling block: save irq state in blkg_lookup_create() dm: don't reuse bio for flushes nvme-pci: trace SQ status on completions nvme-rdma: implement polling queue map nvme-fabrics: allow user to pass in nr_poll_queues nvme-fabrics: allow nvmf_connect_io_queue to poll nvme-core: optionally poll sync commands block: make request_to_qc_t public nvme-tcp: fix spelling mistake "attepmpt" -> "attempt" nvme-tcp: fix endianess annotations nvmet-tcp: fix endianess annotations nvme-pci: refactor nvme_poll_irqdisable to make sparse happy nvme-pci: only set nr_maps to 2 if poll queues are supported nvmet: use a macro for default error location nvmet: fix comparison of a u16 with -1 blk-mq: enable IO poll if .nr_queues of type poll > 0 blk-mq: change blk_mq_queue_busy() to blk_mq_queue_inflight() blk-mq: skip zero-queue maps in blk_mq_map_swqueue ...

Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next

2018-12-27T21:04:52+00:00

Pull networking updates from David Miller: 1) New ipset extensions for matching on destination MAC addresses, from Stefano Brivio. 2) Add ipv4 ttl and tos, plus ipv6 flow label and hop limit offloads to nfp driver. From Stefano Brivio. 3) Implement GRO for plain UDP sockets, from Paolo Abeni. 4) Lots of work from Michał Mirosław to eliminate the VLAN_TAG_PRESENT bit so that we could support the entire vlan_tci value. 5) Rework the IPSEC policy lookups to better optimize more usecases, from Florian Westphal. 6) Infrastructure changes eliminating direct manipulation of SKB lists wherever possible, and to always use the appropriate SKB list helpers. This work is still ongoing... 7) Lots of PHY driver and state machine improvements and simplifications, from Heiner Kallweit. 8) Various TSO deferral refinements, from Eric Dumazet. 9) Add ntuple filter support to aquantia driver, from Dmitry Bogdanov. 10) Batch dropping of XDP packets in tuntap, from Jason Wang. 11) Lots of cleanups and improvements to the r8169 driver from Heiner Kallweit, including support for ->xmit_more. This driver has been getting some much needed love since he started working on it. 12) Lots of new forwarding selftests from Petr Machata. 13) Enable VXLAN learning in mlxsw driver, from Ido Schimmel. 14) Packed ring support for virtio, from Tiwei Bie. 15) Add new Aquantia AQtion USB driver, from Dmitry Bezrukov. 16) Add XDP support to dpaa2-eth driver, from Ioana Ciocoi Radulescu. 17) Implement coalescing on TCP backlog queue, from Eric Dumazet. 18) Implement carrier change in tun driver, from Nicolas Dichtel. 19) Support msg_zerocopy in UDP, from Willem de Bruijn. 20) Significantly improve garbage collection of neighbor objects when the table has many PERMANENT entries, from David Ahern. 21) Remove egdev usage from nfp and mlx5, and remove the facility completely from the tree as it no longer has any users. From Oz Shlomo and others. 22) Add a NETDEV_PRE_CHANGEADDR so that drivers can veto the change and therefore abort the operation before the commit phase (which is the NETDEV_CHANGEADDR event). From Petr Machata. 23) Add indirect call wrappers to avoid retpoline overhead, and use them in the GRO code paths. From Paolo Abeni. 24) Add support for netlink FDB get operations, from Roopa Prabhu. 25) Support bloom filter in mlxsw driver, from Nir Dotan. 26) Add SKB extension infrastructure. This consolidates the handling of the auxiliary SKB data used by IPSEC and bridge netfilter, and is designed to support the needs to MPTCP which could be integrated in the future. 27) Lots of XDP TX optimizations in mlx5 from Tariq Toukan. * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1845 commits) net: dccp: fix kernel crash on module load drivers/net: appletalk/cops: remove redundant if statement and mask bnx2x: Fix NULL pointer dereference in bnx2x_del_all_vlans() on some hw net/net_namespace: Check the return value of register_pernet_subsys() net/netlink_compat: Fix a missing check of nla_parse_nested ieee802154: lowpan_header_create check must check daddr net/mlx4_core: drop useless LIST_HEAD mlxsw: spectrum: drop useless LIST_HEAD net/mlx5e: drop useless LIST_HEAD iptunnel: Set tun_flags in the iptunnel_metadata_reply from src net/mlx5e: fix semicolon.cocci warnings staging: octeon: fix build failure with XFRM enabled net: Revert recent Spectre-v1 patches. can: af_can: Fix Spectre v1 vulnerability packet: validate address length if non-zero nfc: af_nfc: Fix Spectre v1 vulnerability phonet: af_phonet: Fix Spectre v1 vulnerability net: core: Fix Spectre v1 vulnerability net: minor cleanup in skb_ext_add() net: drop the unused helper skb_ext_get() ...

Merge branch 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2018-12-26T21:07:19+00:00

Pull RCU updates from Ingo Molnar: "The biggest RCU changes in this cycle were: - Convert RCU's BUG_ON() and similar calls to WARN_ON() and similar. - Replace calls of RCU-bh and RCU-sched update-side functions to their vanilla RCU counterparts. This series is a step towards complete removal of the RCU-bh and RCU-sched update-side functions. ( Note that some of these conversions are going upstream via their respective maintainers. ) - Documentation updates, including a number of flavor-consolidation updates from Joel Fernandes. - Miscellaneous fixes. - Automate generation of the initrd filesystem used for rcutorture testing. - Convert spin_is_locked() assertions to instead use lockdep. ( Note that some of these conversions are going upstream via their respective maintainers. ) - SRCU updates, especially including a fix from Dennis Krein for a bag-on-head-class bug. - RCU torture-test updates" * 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (112 commits) rcutorture: Don't do busted forward-progress testing rcutorture: Use 100ms buckets for forward-progress callback histograms rcutorture: Recover from OOM during forward-progress tests rcutorture: Print forward-progress test age upon failure rcutorture: Print time since GP end upon forward-progress failure rcutorture: Print histogram of CB invocation at OOM time rcutorture: Print GP age upon forward-progress failure rcu: Print per-CPU callback counts for forward-progress failures rcu: Account for nocb-CPU callback counts in RCU CPU stall warnings rcutorture: Dump grace-period diagnostics upon forward-progress OOM rcutorture: Prepare for asynchronous access to rcu_fwd_startat torture: Remove unnecessary "ret" variables rcutorture: Affinity forward-progress test to avoid housekeeping CPUs rcutorture: Break up too-long rcu_torture_fwd_prog() function rcutorture: Remove cbflood facility torture: Bring any extra CPUs online during kernel startup rcutorture: Add call_rcu() flooding forward-progress tests rcutorture/formal: Replace synchronize_sched() with synchronize_rcu() tools/kernel.h: Replace synchronize_sched() with synchronize_rcu() net/decnet: Replace rcu_barrier_bh() with rcu_barrier() ...

tracing: Use the return of str_has_prefix() to remove open coded numbers

2018-12-23T03:52:30+00:00

There are several locations that compare constants to the beginning of string variables to determine what commands should be done, then the constant length is used to index into the string. This is error prone as the hard coded numbers have to match the size of the constants. Instead, use the len returned from str_has_prefix() and remove the open coded string length sizes. Cc: Joe Perches Acked-by: Masami Hiramatsu (for trace_probe part) Acked-by: Namhyung Kim Signed-off-by: Steven Rostedt (VMware)

tracing: Have the historgram use the result of str_has_prefix() for len of prefix

2018-12-23T03:52:09+00:00

As str_has_prefix() returns the length on match, we can use that for the updating of the string pointer instead of recalculating the prefix size. Cc: Tom Zanussi Acked-by: Namhyung Kim Signed-off-by: Steven Rostedt (VMware)

tracing: Use str_has_prefix() instead of using fixed sizes

2018-12-23T03:51:54+00:00

There are several instances of strncmp(str, "const", 123), where 123 is the strlen of the const string to check if "const" is the prefix of str. But this can be error prone. Use str_has_prefix() instead. Acked-by: Namhyung Kim Signed-off-by: Steven Rostedt (VMware)

tracing: Use str_has_prefix() helper for histogram code

2018-12-23T03:51:01+00:00

The tracing histogram code contains a lot of instances of the construct: strncmp(str, "const", sizeof("const") - 1) This can be prone to bugs due to typos or bad cut and paste. Use the str_has_prefix() helper macro instead that removes the need for having two copies of the constant string. Cc: Tom Zanussi Acked-by: Namhyung Kim Signed-off-by: Steven Rostedt (VMware)

tracing: Make function ‘ftrace_exports’ static

2018-12-22T13:21:06+00:00

In commit 478409dd683d ("tracing: Add hook to function tracing for other subsystems to use"), a new function ‘ftrace_exports’ was added. Since this function can be made static, make it so. Silence the following warning triggered using W=1: kernel/trace/trace.c:2451:6: warning: no previous prototype for ‘ftrace_exports’ [-Wmissing-prototypes] Link: http://lkml.kernel.org/r/20180516193012.25390-1-malat@debian.org Signed-off-by: Mathieu Malaterre Signed-off-by: Steven Rostedt (VMware)